Self-healing ionic gels for wearable strain sensors: synthesis, characterization, and applications in human motion detection
摘要
As the demand for wearable electronic devices, E-skin, and medical intelligence increases year by year, artificial skin with the complex functions of biological skin is attracting more and more attention. In this work, a novel kind of ionic gels with good self-healing performance was prepared using n-butyl acrylate (BA), vinyl imidazole (VI), and the 1-butyl-3-methylimidazole bis(trigonometrical) sulfide ([BMIM][TFSI]) ionic liquid by radical photo-polymerization. The results show the occurrence of π–π packing effects among the imidazole groups in the ionic gels. The glass transition temperature and mechanical properties could be easily adjusted by controlling the [BMIM][TFSI] content. In particular, the BMB0.4 sample showed good fatigue resistance. Moreover, its mechanical properties and ionic conductivity could be essentially restored within 6 hours at room temperature. The good ionic conductivity, strain sensitivity, and reliable stability of these ionic gels indicate that they can be applied to wearable strain sensors and are expected to be widely used in human motion detection systems.